Hi, Good Day! I am using Nintex forms in SharePoint Online. How can I attach files in RTF fields? I mean I have several RTF fields and in each RTF fields user should be able to attach files. It is not work. Is there any solution to this?

You would use the file attachment control in Nintex forms to upload it. It uploads it to the attachments folder in SharePoint, not the RTF field. You can use javascript if you want to get the attachment link from the item, but this is not an out of the box thing.

If you view the form after you added attachments, you should see a link to the attachment in view or display mode of the form.